TED Case Studies: Lake Victoria

1. The Issue

The recent history of Lake Victoria is one of dramatic change
in limnological parameters and native fishery stocks from late
1960s to the present. Over fishing, exotic species introductions,
deleterious land use practices, and pollution from various sources
all contributed to the oxygen depletion and mass extinction of
indigenous fishes now taking place. The question is an urgent one
for scientists, policymakers, and development organizations
worldwide. The current export boom from the lakežs shallow (less
than 80 meters at its deepest), murky, and oxygen-depleted waters
has come at enormous ecological and social cost. The price
includes a massive loss of native species, partially caused by the
introduced perch, and the increasing conversion of the fishery to
an export commodity rather than local protein source. Hence, Lake
Victoria is in danger of becoming the world's largest pool of dead
water. Already half its native fish are extinct, and the 30
million people who eke out a living from its troubled waters are
facing calamity.
2. Description
In 1858, the British explorer John Speke stumbled onto its
southern shore and proclaimed he had discovered the fabled source
of the Nile. In 1875 another British adventurer, Henry Stanley,
circumnavigated Lake Victoria to confirm Speke's claim and spent
two weeks spinning tales of God and England to curry favor with
Mtesa, king of Buganda and ruler of the northern lake region. Then
Stanley sent word back to England, calling for missionaries. They
came with soldiers and traders. Within 20 years England had taken
charge of what became Uganda and Kenya (Germany got Tanzania), and
by 1902 the colonial government had pushed through a railroad from
Mombasa to the lake. Europeans soon denuded vast tracts of forest
in Lake Victoria's watershed to plant tea, coffee, sugar, tobacco,
and cotton. The human population exploded, and people increasingly
turned to the lake not for subsistence but to satisfy a market for
fish--especially the tasty tilapia called ngege--in the growing
urban centers.
Fishing pressure on the lake began to intensify in 1905 when
the British introduced flax gill nets, which soon replaced the
local villagers' papyrus nets and fish traps. With overfishing,
catch sizes began to drop; fishermen turned to nets with ever
smaller mesh sizes and thus decimated both the breeding adults and
young of many native species. By the 1950s the ngege was
commercially extinct and the labeo was not far behind. To
compensate, British officials decided to stock the lake with new
fish. The first nonnative species of tilapia (Cichlidae), that
prospered was the Nile tilapia, Oreochromis niloticus, which feeds
on the minute forms of plant and animal life called plankton,
introduced in the early 1950s. In 1955 the Nile Pearch Lates
nicloticus (Centropomidae) was introduced into Lake Kioga, and when
a few years later it was found in Lake Victoria, steps were taken
to ensure its establishment there.
Despite such changes, the haplochromines appeared to be
thriving in the 1950s. In fact, they appeared so robust that some
colonial administrators favored introducing a big predator like the
Nile perch to eat what they considered bony little "trash" fish and
"convert the haplochromine biomass" into something more able for
the restaurant table. Ecologists, fearing the worst for local
species, strongly opposed the predator. But in 1954 illicit Nile
perch began appearing in commercial catches anyway. Since the
dirty deed was done, officials actively stocked the lake with perch
in the early 1960s. (Ogari suspects perch were first slipped into
the lake by colonial sportsmen, just as homesick British anglers
put trout into highland streams throughout eastern and southern
Africa.) Still, for the next decade or so, the alien perch
population remained small. A United Nations-sponsored survey
completed in 1971 found that haplochromines still made up the
traditional 80 percent of the lake's fish biomass.
Then came what Pereti Basasibwaki, a Fisheries Research
Institute biologist, calls the dark period, the years between 1974
and 1979 when Amin cut off access to the lake. Until 1978, Nile
Perch remained a very small proportion of the commercial catch,
less than 5 percent. It wasn't until 1979 that the Kenyan
government took over the idle Kisumu facility and work resumed
under ICMFRI's auspices. Pilot surveys suggested the lake's fish
biomass was unchanged: it still appeared to consist of 80 percent
haplochromines and less than 2 percent Nile perch. But in 1980 an
abrupt change showed up in Kenyan waters, and within two years it
appeared in Ugandan and Tanzanian waters too. Nile perch suddenly
jumped to 80 percent of the biomass, and haplochromines dropped to
1 percent. Ngege, already rare, virtually disappeared. Clearly
something had been building during the unmonitored 1970s to cause
such a massive explosion of perch. As for the haplochromines, the
leading theory is that they simply provided the predator's fodder.
However, when Nile Perch were introduced into Lake Victoria some 30
years ago to improve game fishing, few would even have guessed that
it might cause the elimination of whole species and the
degradation of the area surrounding the lake. Then in 1978 a very
rapid expansion of the proportion accounted for by Nile Perch took
place, with the result that by 1990 the commercial catch had a
totally different composition, dominated by Nile Perch (almost 60
percent) and Omena (most of the remaining 40 percent). The
haplochromines, and the mixture of other fish had virtually
vanished from the commercial catch.
In the early 1980s, however, few government officials in
Africa viewed the shift in Lake Victoria's fish fauna as a
disaster. The bottom waters of the lake appeared to be a dead
zone, devoid of oxygen and fish life. On the other hand, the lake
was chockfull of algae--five to ten times more than in the early
1960s. That suggested massive eutrophication, an oxygen-depleted
condition caused by high levels of nutrients that encourage the
rapid growth of plankton, especially plant plankton such as algae.
The decay of plankton in turn depletes water of oxygen.
Water quality in Lake Victoria has declined greatly in the
past few decades, owing chiefly to eutrophication arising from
increased inflow of nutrients into the lake. Nutrient inputs have
increased two to three-fold since the turn of the century, mostly
since 1950. Concentrations of phosphorus have risen markedly in the
deeper lake waters, and nitrogen around the edges. Stimulated by
these and other nutrients, the five-fold increase in algal growth
since 1960, and the shift in its composition towards domination by
blue-green algae, is causing deoxygenation of the water, increased
sickness for humans and animals drawing water from the lake,
clogging of water intake filters, and increased chemical treatment
costs for urban centers. Aside from the near-total loss of the
deepwater species, the deoxygenation of the lakežs bottom waters
now poses a constant threat, even to finish in shallower portions
of the lake, as periodic upwelling of hypoxic water causes massive
fish kills. The increased nutrient loads have also spurred the
water hyacinth infestations.
In addition, massive blooms of algae have developed, and come
increasingly to be dominated by the potentially toxic blue-green
variety. The distance at which a white disc is visible from the
surface, (a transparency index measuring alga abundance), has
declined from 5 meters in the early 1930s to one meter or less for
most of the year in the early 1990s. Water-born diseases have
increased in frequency. Water hyacinth, absent as late as 1989,
has begun to choke important waterways and landings, especially
Uganda. Over fishing and oxygen depletion at lower depth of the
lake threaten the artisanal fisheries and biodiversity (over 200
indigenous species are said to be facing possible extinction.)
Scientists advance two main hypothesis for these extensive changes.
First, the introduction of Nile perch as an exotic species some 30
years ago has altered the food web structure; second, nutrient
inputs from adjoining catchments are causing euthrophication.
Thus, although the lake and its fishery show the evidence of the
dramatic changes in the lake basin over the past century, the lake
is not the source of the problem, but the problem went largely
unrecognized amid the wrenching social upheavals of East Africa.
The problem have arisen in the surrounding basins through human
activity.
Some areas of the rivers feeding the lake and the shoreline
are particularly polluted by municipal and industrial discharges.
Some information has been collected by local and national
authorities on the scale and location of polluting industries, and
there are a number of basic industries that are common to most of
the major urban areas, for example, breweries, tanning, fish
processing, agroprocessing (sugar and coffee) and abattoirs. Some
of these have implemented pollution management measures but in
general the level of industrial pollution control is low. Small
scale gold mining is increasing, in Tanzania in particular, and
this is leading to some contamination of the local waterways by
mercury which is used to amalgamate and recover the gold. Some
traces of other heavy metals, such as chromium and lead, are also
found in the lake, although the problem has not yet reached major
proportions.
Finally, the lake basin is used as a source of food, energy,
drinking and irrigation water, shelter, transport, and as a
repository for human, agricultural and industrial waste. With the
populations of the riparian communities growing at rates among the
highest in the world, the multiple activities in the lake basin
have increasingly come into conflict. This has contributed to
rendering the lake environmentally unstable. The lake ecosystem
has undergone substantial, and to some observers alarming changes,
which have accelerated over the last three decades.
3. Related Cases
ZAMBIA CaseZAMCOPP CaseBALLAST CaseTILAPIA CaseNILECROC CaseIVORYWD CasePERCH CaseRHINO CaseRHINOBLK CaseUSCHINA Case
Keyword Clusters
(1): Trade Product = Fish [FISH]
(2): Bio-geography = SPLS
(3): Environmental Problem = Habitat loss [HBITAT]
4. Draft Author: Marcela Rabi Fall 1996
B. LEGAL Cluster
5. Discourse and Status: AGReement and COMplete
Attempts a fisheries collaboration among Kenya, Tanzania and
Uganda are among the oldest on the continent. As early as 1928, it
was recommended that a unified lake-wide authority for regulation
and for collection of fisheries statistics be set up.
Establishment of the East African Freshwater Fisheries Research
Organization (EAFFRO) in 1947 solidified collaboration, and it was
boosted further with formation of the East African Community in
1967. In the early 1970s, all three countries became members of
the FAO Committee for Inland Fisheries of Africa (CIFA). After the
disappearance of this coordinating mechanism with the end of the
East African Community in 1977, the need for collaboration was felt
so strongly that special CIFA Sub-Committee for Lake Victoria was
set up in 1980. Although this was a useful forum for the three
countries, the difficulty of implementing management measures on a
lake-wide basis due to the design of proposal for the Lake Victoria
Fisheries Organization (LVFO).
6. Forum and Scope: LVFO and REGIONal
The Lake Victoria Fisheries Organization (LVFO) is a
Tripartite Agreement of 1994 that involves Kenya, Tanzania, and
Uganda. In addition, the Global Environmental Facility (GEF) is
developing a project that, for the first time, ensure that regional
fisheries management would operate within a regional framework for
environmental action, rather than having only a commercial
orientation. LVFO would support the GEF project.
7. Decision Breadth: 3 (Kenya, Tanzania, and Uganda)
Each of the three riparian Governments has prepared a National
Environmental Action Plan (NEAP). All three NEAPS acknowledge that
Lake Victoria demands urgent attention through regional
cooperation. The NEAPžs focus on problems such as water pollution,
biodiversity loss, land degradation, and damage to wetlands, all
central concerns for the lake and its catchments. Scientists and
resource management framework may threaten the future viability of
the lake basin. Discussion to broaden regional environmental
cooperation covering the Lake Victoria Basin started in late 1992.
In May 1994 the three Governments decided to enter into agreement
jointly to prepare and implement a Lake Victoria Environmental
Management Program. A tripartite agreement to this effect was
signed August 5, 1994. The essential soundness of this agreement
has been proven during project preparation, and its main
institutional arrangement has been proven during project
preparation, and its main institutional arrangements, which have
worked well, will continue into project implementation.
8. Legal Standing: TREATY
In 1988, the World Conservation Union Red Book of Endangered
Species listed the hundreds of endemic fishes of Lake Victoria
under a single heading: "Endangered." The most exuberant expression
of vertebrate adaptive radiation in the world, the haplochromine
species, is now in the midst of the first mass extinction of
vertebrates that scientists have ever had the opportunity to
observe, an event as exciting as it is depressing.
III. GEOGRAPHIC Cluster
9. Geographic locations
a. Geographic Ddomain : AFR = Africa
b. Geographic Site : EAFR = Eastern Africa
a. Geographic Impact : UGANDA
Lake Victoria, with a surface area of 68,800 km2 and an
adjoining catchment of 184,000 km2, is the worldžs second largest
body of fresh water, and the largest in the developing world,
second only to Lake Superior in size. Lake Victoria touches the
Equator in its northern reaches, and is relatively shallow,
reaching a maximum depth of about 80 m, and an average depth of
about 40 m. The lakežs shoreline is long (about 3,500 km) and
convoluted, enclosing innumerable small, shallow bays and inlets,
many of which include swamps and wetlands which differ a great deal
from one another and from the lake itself. Because the lake is
shallow, its volume is substantially less than that of other
Eastern African lakes with much smaller surface area. Lake
Victoria holds about 2,760 km3 of water, only 15 percent of the
volume of Lake Tanganyika, even though the latter has less than
half the surface area.
Some 85 percent of the water entering the lake does so from
precipitation directly on the lake surface, the remainder coming
from rivers which drain the surrounding catchment. The most
significant of these rivers, the Kagera, contributes roughly 7
percent of the total inflow, or one half of that over and above
direct precipitation. The Kagera River, which rises in the
highlands of Burundi and Rwanda, forms the border between Rwanda
and Tanzania before turning to the east, and flows for at least 150
km completely in Tanzania territory. It discharges into the lake
just north of the border between Tanzania and Uganda. Some 85
percent of water leaving the lake does so through direct
evaporation from its surface, and the remaining 15 percent largely
by way of the Victoria Nile, which leaves the lake near Jinja in
Uganda, and flows via the Owen Falls, and the Murchison Falls to
join the outflow from Lake Albert; these outflows are the main
sources of the žWhite Nilež.
The lakežs origins are still the subject of scientific
dispute, but it seems likely that it is much more recent than the
other great lakes of eastern Africa. Many of the rivers now
flowing east into Victoria (including Kagera) once flowed west, at
least in the Miocene, Pliocene, and part of the Pleistocene eras
(within the past 2 million years), possibly eventually into the
Nile system, and more recent upthrust of the western side of the
basin is thought to have reversed these rivers, and caused Lake
Victoria to form by flowing eastwards. It is possible that the
lake could have formed as recently as 25,000 to 35,000 years ago,
and recent evidence suggests it may have dried up completely
between 10,000 and 14,000 years ago.
10. Sub-National Factors: Yes
Millons of liters of untreated swege and industrial waste flow
into the Lake Victoria every day from Kisumu, Kenyažs third largest
city, and from Mwanza in Tanzania. Watershed degradation and
agricultural runoff contribute chemicals, nutrients, and sediment.
And from Rwanda came the grisly addition of some 40,000 human
corpuses-war causalities that floated down the Kagera River in May
1994. Nor is the perch the lakežs only alien species problem.
11. Type of Habitat [LAKE]
IV. TRADE Cluster
12. Type of Measure: QUOTA
13. Direct vs. Indirect Impacts: INDIRECT
14. Relation of Measure to Environmental Impact
a.Direct Related : Yes Fish
b.Indirectly Related : Yes Many
c.Not Related : No
d.Process Related : No
15. Trade Product Identification: Fish
The revenues generated by the Nile perch fishery are much
greater than those ever realized from the lake's native species,
but the relationship between changes in the lake's fauna and
changes in revenues generated by the fishery is not a simple one.
Landings data, suggest that the usable productivity of the lake
increased by at least half an order of magnitude over 15 years.
The distribution of wealth resulting from the Nile perch
fishery is also different from that of the original, artisanal
fishery. Some local fisherman may actually be worse off despite
the apparent plenty. Large-scale operations that exploit the
introduced species for foreign currency are doing well. The small-
scale fisherman and fishmongers, who never went hungry and who
relied for their livelihoods on the traditional tastes and
interesting diversity of the native species, are a vanishing breed.
The specter of protein malnutrition in the lake basin has been
raised by socioeconomists, an incredible irony in a place
exporting nearly 200,000 tons of fish protein annually.
In Uganda, for instance, the fishing industry employs 25,000
people and fish accounts for around 60 per cent of animal protein
consumption. On the other hand, both illegal fishing and the
invasion of Uganda's lakes by water hyacinth are threatening fish
stocks in Uganda's lakes, and especially in Lake Victoria.
Fishermen are using nets which trap mature as well as young fish
in large areas of Lake Victoria. Water hyacinth is affecting air
concentration in breeding water, leading to premature deaths. New
fish processing plants are opening on Lake Victoria and more are
licensed but not yet under construction, putting further pressure
on fish stocks in the lake.
16. Economic Data
Kenya, Tanzania and Uganda control 6, 49, and 45 percent of
the lake surface, respectively. The gross economic product of the
lake catchment is in the order of US$3-4 billion annually, and
supports an estimated population of 25 million people at incomes in
the range of US$90-270 per capita p.a. The lake catchment thus
provides for the livelihood of about on third of the combined
populations of the three countries, and about the same proportion
of the combined gross domestic product. With the exception of
Kampla, the capital of Uganda, the lake catchment economy is
principally an agricultural one, with a number of cash crops
including exports of fish) and high level of subsistence fishing
and agriculture. In Kenya and Uganda the areas of coffee and tea
in the catchment are a significant part of those nations major
agricultural imports. The quality of the physical environment is
therefore a fundamental factor in maintaining and increasing the
living standards of the growing population. Although it is not
possible to put a single estimate to the global value of the lake
in sustaining the regional economy, it can be seen that if
deterioration of the lake resulted in a (say) 5 percent reduction
in productivity of the region, the consequent loss would be of the
order of US$150 million annually.
17. Impact of Measure on Trade Competitiveness: Low
18. Industry Sector: [FOOD]
Until recently, the native fish of Lake Victoria were
harvested by small-scale fishers and processed and traded by women
for local consumption. This kept the nutritional and economic
benefits in the lakeside communities. Today, the perch are caught
by large commercial operations for export market. Local women a
literally left with the scarps-which they must purchase. Deprived
of work and unable to afford this higher priced (and less
palatable) catch, local people face a serious nutritional
predicament. The perch take over has decimated the primary
economic and nutritional resource of 30 million people.
19. Exporter and Importer: Kenya, Uganda, & Tanzania and Many
Many powerful people in the fishery business, for example,
consider the Nile perch a savior, not an ecological disaster, since
the lake is producing record numbers of perch that are bringing in
sorely needed export dollars. On the open lake, where local
fishermen cannot pole their canoes, large boats are hauling out
Nile perch by the uncounted and unregulated ton. The fish are then
sold to dozens of processing plants built along the Kenyan and
Ugandan shores by investors from Asia, Europe, and Australia.
Within hours the thick white fillets have been cut from the fish,
flash frozen, boxed, and loaded on trucks headed for the port of
Mombasa, Kenya, where they are shipped to the tables of Europe and
the Middle East.
E. ENVIRONMENTAL Cluster
1. Environmental Problem Type: Habitat Loss [HABIT]
Over-fishing, exotic species introductions, deleterious land-
use practices, and pollution from various sources all contributed
to the oxygen depletion and mass extinction of indigenous fishes
now taking place. Therefore, the entire lake has been placed in
jeopardy by profound changes in the structure and dynamics of the
ecosystem. 21. Name, Type, and Diversity of Spices
To understand Lake Victoria, one must see both the lake and
its fauna in the context of its giant East African neighbors, Lake
Malawi and Lake Tanganyika. The faunas of all three lakes exhibit
the products of rapid speciation from very few ancestors. Best
known is the fish family Cichlidae, of which more than 90% of the
species in each lake are endemic (Greenwood 1984).
Catfish, mormyrids (elephant-nosed electric fishes), carps,
gastropod and bivalve mollusks, insects, and crustaceans also have
produced clusters of endemic species, but, with the possible
exception of the Lake Tanganyika gastropods, these radiations are
much less diverse and morphologically varied than those of the
cichlids. Closely related but less species-rich cichlid flocks also
occur in the nearby, smaller lakes Edward, George, Kivu, Kyoga, and
Nabugabo (Greenwood 1974, 1981).
The cichlid faunas in the three great lakes in East Africa are
strikingly similar and often cited as examples of evolutionary
parallelism (Eccles and Trewavas 1989, Fryer and Iles 1972, Witte
1984). Three apparent lineages are present in the lakes:
haplochromines, tilapiines, and lamprologines. The haplochromines
are a species-rich and geographically widespread lineage. The
tilapiines are species poor but also widespread. The lamprologines
are species rich, but in the great lakes occur only in Lake
Tanganyika.
As a group, the cichlids stand in contrast to the Nile perch
and Omena, both of which invest heavily in fecundity and little in
parental care. The life history profile of cichlids in general
entails small broods and extended parental care. Most East African
haplochromine and tilapiine cichlids brood relatively few (5 to
100) large eggs and develop their young in the mouth, but the
substratum-spawning lamp-rologines and tilapiines place large
clutches(hundreds to thousands) of small eggs in nests on the lake
bottom. All defend their young until they are self-sufficient.
They have limited dispersal (except for seasonal inshore movements
to spawn or release young) and strong site attachment--
characteristics that should in theory make them highly vulnerable
to extinction (Jablonski 1986, Gaston and Lawton 1990).
Curiously, this view is sharply at odds with certain other of
the cichlids' attributes. They are aggressive, behaviorally and
physiologically adaptable, phenotypically plastic, and prone to
extraordinary evolutionary diversification (Avise 1990, Fryer and
Iles 1972, Liem 1974). Much of this versatility has been attributed
to a fundamental reorganization of the pharyngeal jaws that
cichlids share with several closely allied fish families (Kaufman
and Liem 1992).
Many cichlids can individually alter tooth and skull
morphology in response to a change in diet (Greenwood 1965, Kaufman
1989, Meyer 1990, Sackley 1991, Witte et al. 1990). One cichlid,
the Victorian snail-crusher Astatoreochromis Alluaudi, was
introduced to West Africa to help control the snail vectors for
bilharzia, but these cichlids fed on insects instead of snails and
stopped producing the massive dentition and musculature necessary
to crush snail shells (Sloot-weg 1987).(1)
Cichlids have escaped from tropical fish hatcheries into the
canals and evercase of south Florida, where they reproduce more
successfully than do native sunfishes (Centrarchidae; Courtenay and
Robins 1973, Hogg 1976, Taylor et al. 1984). Introduced all over
the world as a ready source of home-grown protein for developing
nations, tilapiine cichlids may have affected hundreds of native
fish communities.
In short, cichlids have adapted to an incredibly wide
range of conditions. One might expect such adaptability and
ecological versatility to offer some measure of protection against
extinction. That it has not done so in Lake Victoria may be one
indication of the magnitude of change that has taken place.
A fishery that once drew on hundreds of species, mostly
endemic, now rests on three: a native pelagic minnow called the
Omena (Rastrineobola argentea) or Dagaa in Tanzania; the introduced
Nile perch (Lates niloticus), known as Mbuta; and the introduced
Nile tilapia, Orechromis niloticus.
Although there are many features of Lake Victoria which are of
intense interest to biologists, it is fish that received the most
attention. Most of the fish species now in the lake also lived in
the preceding, west-flowing rivers, but the cichlids, in
particular, had a remarkable burst of speciation in response to the
change from river to lake conditions. Similar things happened in
other great lakes, but in Lake Victoria it happened much more
recently, more rapidly, and with at first sight, less opportunities
for ecological isolation in different types of habitat. The
cichlids are capable of rapid genetic change, and more prone to
speciation than other groups of Africa fish. There are more than
200 endemic species and 4 endemic genera of cichlids in Lake
Victoria, more than 150 species of which are of the genus
Haplochromis. Another major lineage is the tilapiines. From the
primitive insect-eating types, mouths and pharynxes have evolved to
allow feeding on plants, mollusks, fish, and even the eggs and
young larvae carried in mouth of brooding females of most cichlid
species.
The non-cichlid fishes have also changed, and there are at
least 50 species, of which 29 are endemic, and one endemic genus.
The non-cichlids show much less divergence from the riverine stock
than is the case with non-cichlid fish in Lake Tanganyika, which
has had a much longer time for them to diversify. While most of
the species remain year round in the lake, there are a number of 13
species) of anadromous (ascending) fish, especially cyprinids,
characids and siluroids, which swim up the rivers when they are in
flood, breed in a suitable place, and return with their young fish
to the lake as the level drops.
22. Impact and Effect: HIGH and [STRCT]
The most important freshwater food fishes in East Africa have
already vanished from the marketplaces and very nearly from the
planet. Scientists, fishermen, and environmentalists have decried
the loss of Lake Victoria's native species, and others have
praised the introduction of Nile perch. Now the Nile perch
threatens to destroy itself, the lake ecosystem, and a major source
of protein in the midst of the world's fastest-growing human
population. In Lake Victoria, as elsewhere, human welfare is
intimately linked to concern for species conservation and ecosystem
integrity.
23. Urgency and Life Time: High
The recent history of the fishes of Lake Victoria, East
Africa, exemplifies a pace and magnitude of change that is
alarming. In 1988, the World Conservation Union Red Book of
Endangered Species listed the hundreds of endemic fishes of Lake
Victoria under a single heading: "Endangered." The most exuberant
expression of vertebrate adaptive radiation in the world is now in
the midst of the first mass extinction of vertebrates that
scientists have ever had the opportunity to observe, an event as
exciting as it is depressing. Thus the most important freshwater
food fishes in East Africa have already vanished from the
marketplaces and very nearly from the planet.
24. Substitutes: Yes
Already researchers like Kaufman, Ochumba, and Basasibwaki are
working on projects to help both people and native fish, regardless
of what happens to the lake itself. Breeding stocks of 40
haplochromine species--selected to represent most of the different
feeding strategies that evolved in the lake--as well as the native
ngege are safe in exile at 30 aquariums in the United States and
Europe under a World Conservation Union program led by Kaufman.
Both Kenya and Uganda are expanding their fish-farming efforts,
collecting founder stocks of haplochromines and other native fishes
and considering plans to introduce them into smaller lakes and
ponds in the region. If the decline of Lake Victoria itself can be
halted, isolated bays and inlets may one day be cordoned off with
nets as "fish parks" or as farms for valuable commercial species.
In addition, a major cooperative effort among all three lakeside
countries -Uganda, Kenya, and Tanzania-was recently launched -the
Lake Victoria Environmental Management Program- which will focus on
water quality, land use management, restoration of indigenous food
fish, control of Nile perch and water hyacinth, and community-based
enforcement. Successful methods developed in pilot zones around
the lake during previous years will then be applied to larger
areas. VI. OTHER Factors
25. Culture: Yes
The business boom is taking a toil on humans as well as fish.
Traditional ways of life along the shore are crumbling. As Ochumba
drives from Kusa Bay back to Kisumu, he stops on Kisumu's outskirts
to talk with women frying perch scraps over charcoal fires. These
women from nearby fishing communities once bought native tilapia,
labeo, and haplochromines to dry in the sun and sell. As these
species dwindled, the women migrated to squatter camps near the
perch-processing plants, where they buy the carcasses after
filleting. The fleshy heads and tails are fried and sold from
roadside pole stands; they are the only fish most local people can
afford. In fact, if the lake continues to deteriorate and the
overfished perch population crashes, it's not clear what anyone who
depends on Victoria will eat.
At first, official concern focused on problems the perch
created on shore. Fishermen needed bigger gear to deal with a fish
that could grow to a hefty six feet. Villagers didn't know how to
fillet or cook the big oily thing and couldn't dry it in the sun.
There were no markets for the monster, prices were low, and most
perch were left on the beach to rot. With UN funds, a Kenya Marine
Fisheries Research Institute (KMFRI) team toured lakeside villages
and Nairobi hotels, demonstrating how to fillet, freeze, smoke, and
cook the fish. Foreign-aid groups and investors moved in with
processing plants and refrigerated trucks. With the benefit of
hindsight, it's tempting to say the effort was too successful.
Today few people who live by the lake can match the price hotels
and foreign customers are willing to pay for perch--so much so that
the specter of protein malnutrition is being raised in a region
exporting 200,000 tons of fish a year. No part of the perch goes
to waste. A poster at KMFRI offices shows shoes, belts, and purses
made by a Mombasa company from tanned perch hide. In Nairobi's
newspapers front-page ads offer up to six dollars a pound for dried
perch swim bladders, which are sent to England for filtering beer
and wine and to the Orient for making soup stock.
26. Trans-Border: Yes
More than 30 million people who depend on the lake are feeling
the consequences of roller-coaster changes in the fauna and lake
environment. For the fishermen of Kusa Bay, the women selling
perch scraps in Kisumu, and all the rest of the 30 million people
whose fate is tied to the lake, there is no place to turn. Even in
Africa, where epic sagas of famine and upheaval are all too common,
the death of Lake Victoria would bring unparalleled suffering. But
baring doesn't begin to describe the situation that would result if
Lake Victoria no longer provided food or employment for the people
who live around it.
27. Rights: No
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